Abstract [en]

We present apodised Bragg waveguides inscribed in fused silica using a high repetition rate fs laser system. By varying the modulation with a pulse picker, the mean refractive index over the grating length could be kept constant, while the grating strength is varied. Thus, Bragg waveguides with zero crossing Gaussian modulation profile could be demonstrated. The side-lobes were suppressed by about 10 dB compared to a uniform grating.